Dental equipment assemblage



Feb. 1, 1944. w, p, UHLER 2,340,715

' DENTAL EQUIPMENT ASSEMBLAGE Filed May 5, 1942 3 sheetssheet '1 Hal Ihmcntor Q 7 Gttomeg Feb. 1, 1944. ,w p UHLER DENTAL EQUIPMENT ASSEMBLAGE 3 Sheets-Sheet Filed May 5, 1942 la at HH WI Jnveritor 7 BB v.

. rm a U. w m m m Patented Feb. 1, 1944 2,340,715 7 DENTAL EQUIPMENT ASSEMBLAGE Wilmer P. Uhler, Tottenville, N. Y., assig'nor to The S. S. White Dental Manufacturing Company, a corporation of Pennsylvania Application May 5, 1942, Serial-No. 441,794

6 Claims.

My invention relates particularly tothat class of. dental equipment assemblages that comprise a stand or pedestal adapted to be placed at the side of a dental chair and within convenient reach of the operator for supporting various equipment and devices that may be employed by both theoperator and the patient in the chair, and is especially directed'to'the upper end or head portion of said stand or pedestal and including the motor anddental engine support.

It has been found in practice that wherein the electric motor has been supported at its lowermost end and remote from the driving end connection of the armature shaft, vibrations incident to the rotation of the armature have been magnified at the region of the connection between the driving shaft andvthe connected driven elements.

The principal objects of my invention are to provide supporting connections for an electric motor that are so disposed in relation to the driving end of the armature shaft as to tend to reduce, at the connection between said driving shaft and driven elements, any vibrations incident to the rapid rotation of the armature.

Other objects of my invention are to provide means for supporting an electric motor that are so arranged. as to afford free and easy access to the wiring connections leading to the motor, while said motor is in its operative position.

Further objects of my invention are to provide motor mounting means comprising a swing able cradle whereby the motor may be suspended and swung free of the support and connected parts for convenient inspection, repair or re placement, and when swung back to its operative position may be conveniently locked to prevent its. accidental displacement.

My invention includes convenient connecting means whereby the driving end of the motor armature shaft may be readily connected and diconnected with the driven element when occasion requires thatthe motor and its supporting cradle be swung free of the supporting frame.

My invention comprises a supporting frame forming theupper part of a dental equipment stand or pedestal and providing means upon which a dental engine assembly may b conveniently mounted for easy connection with the upwardly directed driving end portion of the armature shaft of an electric motor which is removably and .replaceably suspended from a swingable cradle by resilient supports connected with themotor casing at or near its upper end region.

My invention comprehends the cooperative combination between the resilient motor mountings, the resilient coupling between the. motor shaft and the shaft ofthe driven elements, and the resilient. bearing mounting in which the shaft of the driven elements rotates.

My'invention also includes all of the various novelfeatures of construction and arrangement as hereinafter mor definitely specified.

In the accompanyingdrawings, Figure lvis a fragmentary side elevational view showing the upper portion of a dental equipment stand'to which my invention is particularly applicable, and which includes a dental engine mounted thereon; Fig. 2 is a. plan view of the upper section of the equipment stand frame, showing the cradle from which the electric motor is. suspended, a fragment of said frame being broken awayfor convenience of illustration; Fig. 3 is a side elevational view of the structure illustrated in .Fig. 2, a portion being shown in section to illustrate the resilient means whereby the -motor is attached to themotor supporting cradle; and Fig.4 is a central vertical sectional view of the dental equipment stand structure illustrated in Fig. -1,, and showing the electric motor, its mounting and its connections with the driven elements which effect the actuation of the dental engine.-

In said figures, the dental equipment stand as shown in Fig. 1 is in the form of a pedestal I having. the bracket table arm 2 on which'the bracket table 3 is mounted, and having thedental engine 5- mounted above the dome thereof.

Said pedestal, asshown in Fig. 4, is madeuup of several frame sections, includingthe frame section 8, the latter being the domeor motor supporting section which isenclosed by the easing sections 9 and H). The motor section 8 is superposed upon the skeleton standard frame structure of the pedestal, and comprises the annular floor II from which rise the diametrically opposite U-shaped standards l2 respectively curving inwardly at their upper extremities and merging into the annular head 13, in which'ls formed apocket l5 arranged'to receive specially designeddental engine mountingstructure.

The engine arm mounting includes the engine arm support comprising the hollow cylindrical hub l6 disposed coaxially with the axis of-the assembled standard structure, and having the horizontally disposed flange l1 engaged in said pocket l5 in rigid relation to the motor supporting section 8 by the bolts l9, as shown in Fig. 4..

The hub l6 of the engine arm supportis normally encircled by the spacer sleeve 20 above which the engine arm bearing 2| having the horizontally extending bearing flange 22 is disposed .arm supporting bracket 26 projects radially and slightly upward, and said swivel ring 25 is re tained in rotatable relation to the bearing flange 22 with the interposed bearing washer 21 by the nut 29 in threaded engagement with the upper region of said bearing 2|,

As shown in Fig. 4, the pulley 36, which transmits motion to the dental engine by means of the belt 3|, has its depending shaft 32 which is mounted for rotation in the flexible bearing assembly comprising the bearing sleeve 33 which is rigidly engaged in the bearing retainer 35 which may preferably be staked as at 36 to the tube form flexible mounting comprising the inner ring 31 and the outer ring 38 which are joined together by the annular filler 39 of rubber or other suitable resilient material. The outer ring 39 of said flexible mounting is rigidly engaged against the shoulder 49 in the hub l6 by the nut 4| which is screw threadedly engaged by the threaded annulus 42 which carries the enclosing cap 43 formed of sheet material. The lower end of the shaft 32 is provided with the resilient coupling 45 by which it is operatively connected with the shaft 46 of the motor 41, to be hereinafter described.

From the foregoing, it will be obvious that a bearing mounting is provided that is quite stiff radially or laterally and therefore will amply resist the belt pull on the pulley 39. It is, however, quite flexiblewith respect to angular distortion of the axis or shaft 32. This means that the. lower end of said shaft 32 can yield to movement laterally in any direction quite freely, and, sincethe .shaft 32 is connected to the motor shaft by means of the flexible resilient coupling 45, considerable misalignment may be taken care of as well as providing such a flexible mounting as affords ample resiliency for absorption of vibrations which might otherwise be, transmitted to the unit from the motor.

Referring now more particularly to the motor 41 and its mounting as indicated in Figs. 2, 3 and 4, said motor may preferably be supportedupcn the laterally movable cradle 50 which is mounted to swing outwardly from the pedestal axis on the pintles 5| and 52 which are engaged in suitably provided apertures 55 and 56 in the hinge lugs 59 and 66 projecting inwardly from one of the U-shaped standards [2, as shown in said Figs. 2, 3 and 4.

1 Said cradle 56 extends upwardly from'its pivotal support and includes the horizontally extending motor supporting shelf 6| which is provided with four relatively spaced attachment lugs projecting outwardly and each having an aperture 62 therein provided and having the supporting shoulder 63 which affords the pocket 65, as shown in Fig. 3, in which a substantially thick 'dis'c66 of rubber or other suitable resilient material may be inserted. Said disc 66 is provided with'the spacing sleeve or bushing 61.

The weight of the motor is supported by means of a cupped washer 69 against which the head of the motor supporting screw 19 bears with its threaded shank extended through the sleeve or bushing 61 of the disc 66, into threaded engagement with one of the four bosses 1| which extend upwardly from the bearing end cap 12 at the driving end of said motor 41, in registry with the apertures 62 in the four relatively spaced lugs above referred to, it being understood that each of the said apertures 62 and pocket 65 include similar parts as those above described with respect to the sectioned region illustrated in Fig.3. v H

It may be here noted that the cupped washer 69 bears upon the resilient disc 66 near the aper- ;;ture 62 and as said disc is depressed the area of contact of said cupped washer and disc increases until the resisting force is sufficient to support the weight of the motor. Furthermore, it may be observed thatthe'cupped washer 69 is larger than the aperture 62 so that it serves as a factor of safety in event of deterioration of the resilient disc 66, the motor cannot drop away from the cradle.

The shaft coupling 45, which yieldin ly 0onnects the motor shaft 46 with the depending shaft 32 of the driven elements, comprises the collars 15 and 16 which are connected in axial alinement by the annulus 11 of rubber or other resilient material,-and said collar 15 is engaged with the driven shaft 32 by the set-screw 19 while the collar 16 is engaged with the motor shaft 46 by the set-screw 89 engaging the longitudinally extended slot 90 in said motor shaft.

When it is desired to swing the motor on its cradle out of its normal axial alinement, its shaft 46 may be disconnected from the driven shaft 32 by backing off the set-screw 89 and uplifting the'pulley 36 until the coupling 45 on the driven shaft 32 sufficiently clears the upper end of said motor shaft 46.

The motor cradle 59 is provided with the stop lug 9| which is arranged to engage the U-shaped standard, as best shown in Fig. 2, to cause the motor to axially register with its cooperative elements, and said stop lug 9| is provided with a locking screw 92 in threaded engagement therewith and having a knurled head 93 by said standard.

It will be observed that the pulley 30 is mounted in such a manner that it clears the annulus 42 and therefore does not depend 'upon any adjacent thrust bearing, but the thrust is transmitted through resilient coupling 45 to the motor shaft 46 and therefore to the thrust bearing 95 for said motor shaft 46 at the lower end of the motor casing. The driven shaft 32 is therefore free to move axially in the flexibly mounted bearing and any vibration effects which may be proguced are therefore absorbed and not transmit- My invention is advantageous in that the motor is supported by relatively spaced resilient discs mounted in the motor supporting cradle from whichthe motor is suspended from above its center of gravity so that any vibrations incident to the rotation of the armature will be greatly reduced at the region of connection between the armature shaft and the shaft of the driven eleand thereby to prevent such vibrations from being transmitted to any part of the unit comprising the stand or pedestal.

I do not desire to limit my invention to the precise details of construction and arrangement as herein set forth, as it is obvious that various modifications may be made therein without departing from the essential features of my invention as defined in the appended claims.

Having thus described my invention, I claim:

1. An assemblage of the class described, comprising a motor supporting frame including an electric motor carrying cradle hingedly connected to said supporting frame and arranged to swing outwardly upon a vertical axis, an electric motor yieldingly mounted on said cradle with its armature axis disposed vertically and the drivin end of the armature shaft extended upwardly, yielding supports for said motor connecting its upper region with said cradle whereby the body of said motor freel depends in suspended relation therefrom closely adjacent to the driving end of the motor shaft, a driven element having a relatively alined depending shaft flexibly mounted in said supporting frame, and a readily removable and replaceable resilient coupling arranged to connect said depending shaft with said armature shaft, and cooperative with said yielding supports to suppress vibrations incident to actuation of said motor.

2. An assemblage of the class described, com- 7 prising a motor support, an electric motor suspended therefrom with its center of gravity below its points of support, resilient vibration absorbing means interposed between said motor and its support, an armature shaft projecting upwardly and maintained vertical by said vibration absorbing means, a shaft of the driven elements depending toward said armature shaft substantially in axial alinement therewith, a resilient connector between the opposed relatively spaced armature shaft and driven shaft, joining them to rotate together and tending to maintain them in alinement, and a resilient bearing for said driven shaft, maintaining it against lateral displacement, cooperative through said resilient connector with said resilient vibration absorbing means to prevent vibrations incident to actuation of said motor.

3. An assemblage of the class described, comprising a motor support, an electric motor suspended therefrom, with resilient vibration absorbing means interposed, a thrust bearing in the casing of said motor, an armature shaft rotatable on said thrust bearing and having its opposite driving end projecting upwardly, a driven shaft supporting driven elements depending toward said armature shaft and having its end spaced from the end of said armature shaft, a coupling of resilient material connecting said shafts to rotate in unison, said driven shaft and its connected elements being wholly supported for rotation on said thrust bearing through the resilient coupling and armature shaft.

4. In an assemblage of the class described, the combination with a support, of an electric motor, resilient means interposed between said motor and support, an armature shaft, a driven shaft of substantial length carrying a pulley to which a belt may be connected, a resilient coupling connecting said shafts, and a resilient bearing for said driven shaft so disposed as to yieldingly maintain it against lateral stresses of said belt, whereby the several resilient elements cooperate to absorb any vibrations incident to the rotation of the armature, its shaft and connected parts.

5. An assemblage of the class described, which comprises the upper portion of a dental equipment stand or pedestal, and which comprises a support including an electric motor carrying cradle hingedly connected with said support and arranged to swing upon a vertically disposed axis out of axial alinement with said support, an electric motor yieldingly mounted on said cradle with its armature axis disposed vertically and the driving end of the armature shaft extended upwardly, resilient supports connecting the motor at its upper portion with said cradle whereby the body of said motor freely depends therefrom in suspended relation with its armature shaft maintained vertical, a dental engine assembly mounted on said support, and means comprising a, detachable resilient connection relatively adjacent to said resilient supports and arranged to operatively join said dental engine assembly to the driving end of said armature shaft, said resilient supports and connection being so correlated as to absorb vibrations incident to rotation of said armature and said dental engine parts.

6. An assemblage of the class described, comprising a motor support, an electric motor suspended from said support, a thrust bearing in the casing of said motor, a vertically disposed armature shaft rotatably resting upon said thrust bearing, a vertically extended bearing resiliently mounted in said support, a pulley shaft mounted in said bearing in axial alinement with said armature shaft yieldingly restrained from lateral movement by said bearing, a pulley on the free upper end of said shaft and spaced from said bearing, and a coupling of resilient material connecting said shafts to rotate in unison so that said pulley shaft is wholly supported axially for rotation on said thrust bearing through said resilient coupling and armature shaft.

WILMER P. UHLER. 

